Air NZ 787 Lightning Strike

[FlightlessParrot]

The New Zealand Herald reports today that an Air NZ 787 flying Auckland to Perth was hit by lightning, and had to have repairs at Perth and then be flown back without pax to Auckland for further work Air NZ Dreamliner scorched and grounded in lightning strike - National - NZ Herald News (http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=11366816).

Could I ask whether this is about the same as you'd expect from a lightning strike on an aircraft with conventional/old fashioned construction? Or are lightning strikes so different in their effects that it's silly to try to generalise on one example.

(I know lightning strike was one of the issues people had with composite construction: I know that this was taken into account in the design of the aircraft; I have no preconceptions, just wanting to know.)

[tdracer]

It's difficult to say, since it all depends on the severity of the strike - there are literally orders of magnitude differences between a 'small', a 'large', and a "OMG" lightning strike. It's also dependent on where the strike attaches to the aircraft.
On aluminum aircraft, it's not particularly uncommon for lightning strikes to cause localized damage. On the 787, a metallic mesh (copper, IIRC) is imbedded in the composite matrix during construction to reduce the electrical resistance of the composite structure - but it's resistance is still a bit higher than aluminum structure. This higher electrical resistance is accounted for in the rest of the aircraft. For example the higher resistance means a higher 'induced' electrical voltage in aircraft wiring due to a lightning strike, so the associated electrical systems have been designed for greater lightning induced voltages.

[FlightlessParrot]

Thank you for the reply. I guess part of the delay might be that everyone was wanting to really examine the effects of what is presumably a fairly new event, rather than just getting the aeroplane back in service asap.

[belowMDA]

I think having a black paint finish makes finding any damage that much more difficult too.

[tdracer]

I'm not positive about this, but I think only the first Air New Zealand 787-9 has the all-black paint scheme - follow on aircraft were to be white with black highlights. I'm thinking I read that somewhere when they first rolled out the 'all black' paint scheme. Unfortunately my office is no longer at the Everett facility so I don't get to see the new aircraft coming out of the paint hanger or sitting on the flightline like I was used to :*.